KR20120064126A - Wiring board and method for producing same - Google Patents

Abstract

The wiring board 1000 includes a substrate 100 having a receiving space, a first insulating layer 102 formed on the substrate 100 so as to close an opening of the substrate 100 formed by the receiving space, and a first one. A first rigid wiring board 10 having a first wiring layer 112 formed on the insulating layer, a second rigid wiring board 20 having a second wiring layer 214 on a main surface thereof, and housed in an accommodation space; It has a 1st connection conductor 122 which connects a 1st wiring layer and a 2nd wiring layer, and the 1st interlayer insulation layer 302 formed on a 1st wiring layer.

Description

Wiring board and manufacturing method thereof {WIRING BOARD AND METHOD FOR PRODUCING SAME}

The present invention relates to a wiring board and a method of manufacturing the same.

Patent Literature 1 discloses a multilayer wiring board in which a region having a high wiring density is partially formed. In this wiring board, the second wiring board is bonded to the first wiring board, and the wiring of the first wiring board and the wiring of the second wiring board are electrically connected.

Japanese Laid-Open Patent Publication No. 2003-298234

It is thought that the wiring board of patent document 1 has the following problems.

Since a 2nd wiring board protrudes on the surface of a wiring board, it is thought that the connection reliability of a 1st wiring board and a 2nd wiring board with respect to external shock etc. is low. Because of the poor symmetry of the wiring board, warpage or the like is feared. Since the surface mounting area is not flat, it is considered that the constraints regarding the arrangement of components and the arrangement of wirings are large. In addition, since the first wiring board and the second wiring board are not formed integrally, it is considered necessary to connect the first wiring board and the second wiring board by another method (for example, solder or adhesive).

An object of the present invention is to obtain better electrical characteristics with respect to a connection between a first rigid wiring board and a second rigid wiring board included in a wiring board.

According to a first aspect of the present invention, a wiring board includes a substrate having an accommodating space, a first insulating layer formed on the substrate so as to close an opening of the substrate formed by the accommodating space, and the first insulating layer. A first rigid wiring board having a first wiring layer formed thereon, a second rigid wiring board having a second wiring layer on a main surface thereof and housed in the accommodation space, and a first connection connecting the first wiring layer and the second wiring layer. And a first interlayer insulating layer formed on the first wiring layer.

The manufacturing method of the wiring board which concerns on the 2nd viewpoint of this invention is arrange | positioning the 2nd rigid wiring board which has a 2nd wiring layer on the main surface in the accommodating space provided in the board | substrate of a 1st rigid wiring board, and the said board | substrate and said 2nd rigid By forming an insulating layer on the wiring board, forming a first via hole in the insulating layer, forming a first connecting conductor in the first via hole, and forming a first wiring layer on the insulating layer. Manufacturing the first rigid wiring board having a first wiring layer and accommodating the second rigid wiring board therein, wherein the first via hole is formed in an inner layer of the wiring board, and the first wiring layer and the second wiring layer are It is electrically connected by the said 1st connection conductor.

According to the present invention, better electrical characteristics can be obtained with respect to the connection between the first rigid wiring board and the second rigid wiring board included in the wiring board.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows schematic structure of the wiring board which concerns on embodiment of this invention.
2 is a cross-sectional view illustrating a schematic structure of a second rigid wiring board.
3 is a cross-sectional view illustrating a schematic structure of a first rigid wiring board.
4 is a plan view illustrating an arrangement of a second rigid wiring board.
It is a flowchart which shows the procedure of the manufacturing method of the wiring board which concerns on embodiment of this invention.
6 is a diagram for explaining a step of preparing a second rigid wiring board.
It is a figure for demonstrating the process of arrange | positioning a 2nd rigid wiring board in a storage space.
It is a figure for demonstrating the process of arrange | positioning an insulating layer and copper foil regarding formation of a 1st layer.
9 is a diagram for explaining a pressing step with respect to the formation of the first layer.
FIG. 10 is a view for explaining a step of forming a via hole and a through hole in the first layer.
It is a figure for demonstrating the process of arrange | positioning an insulating layer and copper foil regarding formation of a 2nd layer.
It is a figure for demonstrating the press process regarding formation of a 2nd layer.
It is a figure for demonstrating the process of forming a via hole in a 2nd layer.
It is a figure for demonstrating the plating process and the patterning process regarding formation of a 2nd layer.
It is a figure for demonstrating the process of forming a soldering resist layer.
It is a figure which shows the example in which a 2nd rigid wiring board contains an electronic component.
It is a figure which shows an example of the wiring board which embeds several 2nd rigid wiring board.
18 is a diagram illustrating an example in which the first rigid wiring board and the second rigid wiring board have wiring layers only on one side.
It is a figure which shows the example which a receiving space is a recessed part.
It is a figure (1) for demonstrating the manufacturing method using the semiadditive process.
FIG. 21 is a diagram (2) for illustrating a manufacturing method using the semiadditive process. FIG.
22 is a diagram (3) for illustrating the manufacturing method using the semiadditive process.
It is a figure (4) for demonstrating the manufacturing method using the semiadditive process.
It is a figure (5) for demonstrating the manufacturing method using the semiadditive process.
FIG. 25 is a view for explaining a manufacturing method using a semiadditive process (No. 6). FIG.
It is a figure (7) for demonstrating the manufacturing method using the semiadditive process.
27 is a diagram (8) for illustrating the manufacturing method using the semiadditive process.
28 is a diagram (1) for illustrating a manufacturing method using the transfer method.
29 is a diagram (2) for illustrating a manufacturing method using the transfer method.
30 is a diagram (3) for illustrating the manufacturing method using the transfer method.
31 is a diagram (4) for illustrating the manufacturing method using the transfer method.
Fig. 32 is a diagram for explaining the manufacturing method using the transfer method (No. 5).
33 is a diagram for explaining the manufacturing method using the transfer method (No. 6).
Fig. 34 is a figure for explaining the manufacturing method using the transfer method (No. 7).
FIG. 35 is a diagram (1) for illustrating a wiring board in which wiring layers are connected by through-hole conductors. FIG.
36 is a diagram (2) for illustrating a wiring board in which wiring layers are connected by through hole conductors.

Carrying out the invention  Form for

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described, referring drawings. In addition, arrow Z1, Z2 points out the lamination direction of the wiring board corresponding to the normal line direction (or the thickness direction of a core board | substrate) of the main surface (front and back surface) of a wiring board, respectively. On the other hand, arrows X1, X2 and Y1, Y2 indicate the direction (direction parallel to the main surface of a wiring board) orthogonal to a lamination direction, respectively. The main surface of the wiring board is the X-Y plane. Moreover, the side surface of a wiring board becomes an X-Z plane or a Y-Z plane.

In description of embodiment, two main surfaces facing the opposite normal direction are called 1st surface (surface of arrow Z1 side), and 2nd surface (surface of arrow Z2 side). In the lamination direction, the side close to the core is referred to as the lower layer (or the inner layer side) and the side far from the core is referred to as the upper layer (or the outer layer side). An outer layer means the uppermost layer (outermost layer), and an inner layer means the lower layer (layers other than outermost layer) than an outer layer. The layer containing the conductor pattern which can function as wiring of a circuit etc. is called wiring layer. The wiring layer may include, in addition to the conductor pattern, a land of a through hole conductor or a via conductor. A conductor formed in the through hole and electrically connecting the wiring layers on both sides of the substrate to each other is called a through hole conductor. A conductor formed in the via hole and electrically connecting the upper wiring layer and the lower wiring layer to each other is called a via conductor.

As shown in FIG. 1, the wiring board 1000 of the present embodiment has a low density conductor region R1 and a high density conductor region R2. The conductor density of the high density conductor region R2 is larger than the conductor density of the low density conductor region R1. When the number of wiring layers per unit thickness is compared with respect to the low density conductor region R1 and the high density conductor region R2, the number of wiring layers of the high density conductor region R2 is larger than the number of wiring layers of the low density conductor region R1. In the present embodiment, due to the difference in the number of wiring layers, the presence density of the conductor in the high density conductor region R2 is larger than the existence density of the conductor in the low density conductor region R1.

The low density conductor region R1 and the high density conductor region R2 are each part of the first rigid wiring board 10. Moreover, the 1st rigid wiring board 10 contains the 2nd rigid wiring board 20. As shown in FIG. In the 1st rigid wiring board 10, the 2nd rigid wiring board 20 is corresponded to the high density conductor area | region R2, and the other part is made into the low density conductor area | region R1. Therefore, the present density of the conductor in the second rigid wiring board 20 is higher than the present density of the conductor in the first rigid wiring board 10. The wiring board 1000, the first rigid wiring board 10, and the second rigid wiring board 20 are printed wiring boards, respectively. The second rigid wiring board 20 is a multilayer wiring board including a plurality of wiring layers.

As shown in FIG. 2, the second rigid wiring board 20 includes a substrate 200, insulating layers 201 and 202, wiring layers 211 to 214, and via conductors 221 and 222. The wiring layers 213 and 214 are formed on the main surface (first surface, second surface) of the second rigid wiring board 20. Via conductors 221 and 222 are filled vias. The wiring layers 211 to 214 and the via conductors 221 and 222 are made of copper, for example. In addition, the insulating layers 201 and 202 function as interlayer insulating layers. The insulating layers 201 and 202 consist of hardened prepreg, for example. As the prepreg, for example, epoxy resin, polyester resin, bismaleimide triazine resin (BT resin), imide resin (polyimide), phenol resin or allylated phenyl to base materials such as glass fiber or aramid fiber What impregnated resin, such as a lene ether resin (A-PPE resin), is used.

The board | substrate 200 consists of epoxy resins, for example. It is preferable that an epoxy resin contains reinforcing materials, such as glass fiber and aramid fiber, for example by resin impregnation process. The reinforcing material is a material having a lower coefficient of thermal expansion than the main material (epoxy resin). As a reinforcing material, inorganic materials, such as a glass cloth, a silica filler, or a glass filler, are preferable, for example.

The wiring layer 211 is formed on the first surface of the substrate 200, and the wiring layer 212 is formed on the second surface of the substrate 200. Through holes 200a are formed in the substrate 200. And through-hole conductor 200b is formed in the wall surface of through-hole 200a. The through hole conductor 200b electrically connects the wiring layer 211 and the wiring layer 212 with each other. The through hole 200a is filled with the resin 200c that flows out of the insulating layers 201 and 202, for example. The wiring board which consists of the board | substrate 200, the wiring layers 211 and 212, and the through-hole conductor 200b corresponds to the core board | substrate of the 2nd rigid wiring board 20. As shown in FIG.

An insulating layer 201 is formed on the first surface of the substrate 200, and an insulating layer 202 is formed on the second surface of the substrate 200. The wiring layer 213 is formed on the insulating layer 201, and the wiring layer 214 is formed on the insulating layer 202. Via holes 201a are formed in the insulating layer 201, and via holes 202a are formed in the insulating layer 202. Via holes 201a and 202a are respectively filled with a conductor (for example, copper) by, for example, plating to form via conductors 221 and 222. The wiring layer 211 and the wiring layer 213 are electrically connected to each other via the via conductor 221. In addition, the wiring layer 212 and the wiring layer 214 are electrically connected to each other via the via conductor 222.

As shown in FIG. 3, the 1st rigid wiring board 10 contains the 2nd rigid wiring board 20. As shown in FIG. Moreover, the 1st rigid wiring board 10 has the insulated substrate 103 which consists of the board | substrate 100 and the insulating layers 101 and 102, the wiring layers 111 and 112, and the via conductors 121 and 122. As shown in FIG. The wiring layers 111 and 112 are formed on the main surface (first surface, second surface) of the first rigid wiring board 10.

The board | substrate 100 consists of five insulating layers, ie, insulating layers 100a-100e, for example. The insulating layers 100a to 100e are laminated in the order of the insulating layers 100a, 100b, 100c, 100d and 100e from the first surface toward the second surface. The thickness of the substrate 100 (the sum of the thicknesses of the insulating layers 100a to 100e) is almost the same as the thickness of the second rigid wiring board 20. It is preferable that the thickness of at least one wiring layer of the second rigid wiring board 20 is smaller than the thickness of the wiring layer of the first rigid wiring board 10.

As shown in FIG. 4, a through hole 20b is formed in the substrate 100. And this through-hole 20b becomes accommodating space R11 (accommodating part). An opening is formed in the substrate 100 by the accommodation space R11. As shown in FIG. 3, the second rigid wiring board 20 is accommodated in the accommodation space R11 formed in the first rigid wiring board 10 (substrate 100). The gap between the first rigid wiring board 10 and the second rigid wiring board 20 is filled with the resin 20a flowing out from the surrounding insulating layers (insulating layers 100a to 100e, insulating layers 101 and 102, etc.). do.

The board | substrate 100 and the 2nd rigid wiring board 20 are arrange | positioned side by side in the X direction or the Y direction, as shown in FIG. In FIG. 4, a plurality of rectangular storage spaces R11 are formed in one rectangular first rigid wiring board 10 (substrate 100), and each of these storage spaces R11 is formed. Although the example which arrange | positions the rectangular 2nd rigid wiring board 20 to is shown, it is not limited to this. The number, shape, etc. of the 1st rigid wiring board 10 and the 2nd rigid wiring board 20 are arbitrary.

Insulating layers 100a-100e consist of hardened prepreg, for example. As the prepreg, for example, epoxy resin, polyester resin, bismaleimide triazine resin (BT resin), imide resin (polyimide), phenol resin or allylated phenyl to base materials such as glass fiber or aramid fiber What impregnated resin, such as a lene ether resin (A-PPE resin), is used.

An insulating layer 101 (second insulating layer) is formed on the first surface of the second rigid wiring board 20 and the insulating layer 100a, and the second surface of the second rigid wiring board 20 and the insulating layer 100e is formed. Insulating layer 102 (first insulating layer) is formed. The opening of one (first surface side) of the substrate 100 formed by the through hole 20b is blocked by the insulating layer 101 formed on the first surface side of the substrate 100, and is formed in the through hole 20b. The opening of the other side (2nd surface side) of the board | substrate 100 formed by it is clogged by the insulating layer 102 formed in the 2nd surface side of the board | substrate 100. FIG.

The wiring layer 111 is formed on the insulating layer 101, and the wiring layer 112 is formed on the insulating layer 102. Via holes 101a are formed in the insulating layer 101, and via holes 102a are formed in the insulating layer 102. The via holes 101a and 102a are respectively filled with a conductor (for example, copper) by plating, for example, and the via conductors 121 and 122 are formed. The wiring layer 213 and the wiring layer 111 are electrically connected to each other via the via conductor 121. In addition, the wiring layer 214 and the wiring layer 112 are electrically connected to each other via the via conductor 122. As a result, the low density conductor region R1 and the high density conductor region R2 are electrically connected to each other via the via conductor 121 and the via conductor 122. In the present embodiment, the via conductors 121 and 122 are field vias. In this embodiment, the via conductor 122 corresponds to the 1st connection conductor, and the via conductor 121 corresponds to the 2nd connection conductor.

Through holes 10a are formed in the substrate 100 and the insulating layers 101 and 102. And through-hole conductor 10b is formed in the wall surface of through-hole 10a. The through hole conductor 10b electrically connects the wiring layer 111 and the wiring layer 112 to each other.

As shown in FIG. 1, the wiring board 1000 includes the insulating layers 301 and 302 and the wiring layers 311 and 312 in addition to the first rigid wiring board 10 (including the second rigid wiring board 20). And via conductors 321 and 322 and solder resist layers 331 and 332. Via conductors 321 and 322 are field vias. The wiring board 1000 has a structure in which the via conductors 221, 121, and 321 are stacked (stacked) in the Z direction on the first surface side of the substrate 200, and the via conductor on the second surface side of the substrate 200. 222, 122, and 322 have a structure in which they are stacked (stacked) in the Z direction.

An insulating layer 301 (second interlayer insulating layer) is formed on the first side of the insulating layer 101, and an insulating layer 302 (first interlayer insulating layer) is formed on the second side of the insulating layer 102. do. The through hole 10a is filled with the resin 10c flowing out from the insulating layers 301 and 302.

The wiring layer 311 is formed on the insulating layer 301, and the wiring layer 312 is formed on the insulating layer 302. Via holes 301a are formed in the insulating layer 301, and via holes 302a are formed in the insulating layer 302. The via holes 301a and 302a are respectively filled with a conductor (for example, copper) by plating, for example, and the via conductors 321 and 322 are formed. The wiring layer 111 and the wiring layer 311 are electrically connected to each other via the via conductor 321. In addition, the wiring layer 112 and the wiring layer 312 are electrically connected to each other via the via conductor 322.

A solder resist layer 331 is formed on the first surface of the insulating layer 301, and a solder resist layer 332 is formed on the second surface of the insulating layer 302. Each of the solder resist layers 331 and 332 is made of, for example, a photosensitive resin using an acrylic epoxy resin, a thermosetting resin mainly composed of an epoxy resin, an ultraviolet curable resin, or the like.

An opening 331a is formed in the solder resist layer 331, and an opening 332a is formed in the solder resist layer 332. The external connection terminal 331b is formed in the opening 331a, and the external connection terminal 332b is formed in the opening 332a. The external connection terminal 331b is formed on the wiring layer 311, and the external connection terminal 332b is formed on the wiring layer 312. The external connection terminals 331b and 332b are solder bumps, for example. The external connection terminals 331b and 332b are used for electrical connection with other wiring boards, electronic components, or the like, for example. The wiring board 1000 can be used as a circuit board of a mobile telephone or the like, for example, by being mounted on another wiring board on one side or both sides.

In the wiring board 1000 of this embodiment, the 2nd rigid wiring board 20 is accommodated in the accommodation space R11 of the 1st rigid wiring board 10. In the inner layer of the wiring board 1000, the first rigid wiring board 10 and the second rigid wiring board 20 are electrically connected to each other by the via conductors 121 and 122. That is, in the wiring board 1000, the first rigid wiring board 10 and the second rigid wiring board 20 are integrally formed in the inner layer of the wiring board 1000. For this reason, the connection reliability of the 1st rigid wiring board 10 and the 2nd rigid wiring board 20 is high with respect to external shocks. As a result, cracks are also suppressed.

In the wiring board 1000 of the present embodiment, the first rigid wiring board 10 and the second rigid wiring board 20 are electrically connected to each other via via conductors 121 and 122. For this reason, in the normal manufacturing process, such as formation of the inner layer pattern of the wiring board 1000, formation of the via conductor for interlayer connection, etc., the 1st rigid wiring board 10 and the 2nd rigid wiring board 20 are electrically connected. Can be. Moreover, manufacturing cost and manufacturing time can be reduced by sharing of a manufacturing process. In addition, a separate method (for example, solder or adhesive) is not required for the connection between the first rigid wiring board 10 and the second rigid wiring board 20.

Since the first rigid wiring board 10 and the second rigid wiring board 20 are electrically connected to each other in the inner layer of the wiring board 1000, the surface of the wiring board 1000 is flat and seamless. As a result, the component mounting area or wiring area on the surface of the wiring board 1000 is widened. Moreover, since the wiring distance becomes short compared with the case where the first rigid wiring board 10 and the second rigid wiring board 20 are connected in the outermost layer, the impedance can be reduced. Moreover, the conductor material required for wiring is also reduced. In addition, the influence of signal noise is also reduced.

In the wiring board 1000 of this embodiment, the wiring layers 213 and 214 on both main surfaces of the second rigid wiring board 20 are connected to the first rigid wiring board via the via conductors 121 and 122 of the inner layer of the wiring board 1000. It is electrically connected with the wiring layers 111 and 112 of (10). Therefore, with respect to both surfaces of the wiring board 1000, the above-described effects (impact resistance, improvement in flatness, etc.) are obtained.

Moreover, a wiring layer and an insulating layer are built up on both surfaces of the first rigid wiring board 10 and the second rigid wiring board 20. For this reason, the symmetry (especially symmetry of Z direction) of the wiring board 1000 becomes high, and the curvature of the wiring board 1000 is suppressed.

The wiring board 1000 of the present embodiment partially has a high density conductor region R2 by incorporating the second rigid wiring board 20 having a high conductor density into the first rigid wiring board 10. By doing in this way, the wiring board 1000 can be easily partially pitched.

In the wiring board 1000 of this embodiment, the 1st rigid wiring board 10 and the 2nd rigid wiring board 20 are connected through resin 20a which flowed out from the surrounding insulation layer. Thereby, adhesiveness of the 1st rigid wiring board 10 and the 2nd rigid wiring board 20 improves. In addition, since the resin 20a becomes a buffer material, even when an impact is applied from the outside, the impact is not directly transmitted to the second rigid wiring board 20. This increases the impact resistance of the second rigid wiring board 20.

Since the via conductors 221, 121, and 321 are laminated in the Z direction, the second rigid wiring board 20 can receive the impact from the first surface side. In addition, since the via conductors 222, 122, and 322 are laminated in the Z direction, the second rigid wiring board 20 can receive the impact from the second surface side. This increases the impact resistance of the second rigid wiring board 20.

In the wiring board 1000 of this embodiment, the board | substrate 100 consists of several (5 layer) prepreg layers (insulating layers 100a-100e). For this reason, adjustment of the thickness of the board | substrate 100 is easy. In particular, the substrate 100 having a large thickness can be easily formed.

The wiring board 1000 is manufactured in the order as shown in FIG. 5, for example.

First, in step S10, the insulating layers 100a-100e (substrate 100) which have through-hole 20b (FIG. 4), and the 2nd rigid wiring board 20 are prepared. For example, as shown in FIG. 6, the second rigid wiring board 20 is cut out from the multi-piece substrate 21 having a plurality of (for example, 12) wiring boards (the second rigid wiring board 20). Prepare.

Subsequently, in step S11 of FIG. 5, as shown in FIG. 7, the second rigid wiring board 20 is disposed in the through hole 20b (accommodating space R11) of the insulating layers 100a to 100e. The accommodation space R11 is produced by forming the through-hole 20b in the insulating layers 100a-100e with a laser, for example. In this step, since the insulating layers 100a to 100e are separated from each other, an accommodation space R11 is formed in each of the insulating layers 100a to 100e. Insulating layers 100a-100e are laminated | stacked according to the position of accommodation space R11. It is preferable to make the size of the storage space R11 substantially the same as the size of the 2nd rigid wiring board 20, for example. For example, it is preferable to make the accommodation space R11 larger than the 2nd rigid wiring board 20 by a predetermined margin. In addition, the 2nd rigid wiring board 20 can be manufactured by the well-known buildup method, for example.

Subsequently, in step S12 of FIG. 5, the first rigid wiring board 10 is manufactured. As a result, the second rigid wiring board 20 is embedded in the first rigid wiring board 10.

Specifically, by the process of said step S11, the 2nd rigid wiring board 20 is arrange | positioned in the accommodation space R11. From this state, as shown in FIG. 8, the insulating layer 101 and the copper foil 1001 are arrange | positioned at the 1st surface side of the insulating layer 100a and the 2nd rigid wiring board 20, and the insulating layer 100e and The insulating layer 102 and the copper foil 1002 are arrange | positioned at the 2nd surface side of the 2nd rigid wiring board 20. FIG. In this step, the insulating layers 101 and 102 (prepregs) are in an uncured state.

Then, as shown in FIG. 9, pressure is applied to outermost copper foil 1001, 1002. This press is a hot press, for example. In this press, it is preferable to press the said arrange | positioned member (object of press) between the main parts by the jig for presses positioned with the pin, for example, and to press substantially vertically with respect to the main surface.

As a result, the openings at both ends of the through hole 20b (FIG. 7) are blocked by the insulating layer 101 formed on the first surface side and the insulating layer 102 formed on the second surface side. Moreover, resin 20a flows out from the prepreg which comprises each of the insulating layers 100a-100e and the insulating layers 101,102. The resin 20a is filled in the gap between the insulating layers 100a to 100e and the second rigid wiring board 20. By prepress and heating, each prepreg hardens and a member adheres. The insulating layers 100a to 100e are integrated to form the substrate 100. In addition, you may divide and perform press and heat processing in multiple times. In addition, you may heat-process and press separately.

Subsequently, as shown in FIG. 10, via holes 101a and 102a and through holes 10a are formed by, for example, irradiating a CO ₂ laser. Then, desmear and soft etch are performed as needed.

Subsequently, by plating the panel (e.g., chemical copper plating and electro-copper plating), a plating film is formed on the entire surface of the first and second surfaces, and a predetermined lithography process (e.g., pretreatment, laminate, The plating film is patterned by exposure, development, etching, thin film, and the like. Thereby, the first rigid wiring board 10 as shown in FIG. 3 is manufactured. That is, by this plating, the via conductor 121 is formed in the via hole 101a, the via conductor 122 is formed in the via hole 102a, and the through-hole conductor 10b is formed in the wall surface of the through hole 10a. ) Is formed. The wiring layer 111 is formed on the first surface of the insulating layer 101, and the wiring layer 112 is formed on the second surface of the insulating layer 102. Then, it roughens as needed.

Subsequently, in step S13 of FIG. 5, the wiring layer and the insulating layer are built up on both surfaces of the first rigid wiring board 10.

Specifically, as shown in FIG. 11, the insulating layer 301 and the copper foil 1003 are arranged on the first surface side of the first rigid wiring board 10, and insulated on the second surface side of the first rigid wiring board 10. The layer 302 and the copper foil 1004 are arrange | positioned. In this step, the insulating layers 301 and 302 (prepreg) are in an uncured state.

Subsequently, as shown in FIG. 12, pressure is applied to outermost copper foil 1003, 1004 similarly to the process of FIG. Thereby, resin 10c flows out from the prepreg which comprises each of the insulating layers 301,302. Resin 10c is filled in through hole 10a. By prepress and heating, each prepreg hardens and a member adheres.

Subsequently, as shown in FIG. 13, via holes 301a and 302a are formed by, for example, irradiating a CO ₂ laser. Then, desmear and soft etch are performed as needed.

Subsequently, by plating the panel (for example, chemical copper plating and electrocopper plating), a plating film is formed on the entire surfaces of the first and second surfaces, and as shown in FIG. 14, by a predetermined lithography process. The plating film is patterned. By this plating, the via conductor 321 is formed in the via hole 301a, and the via conductor 322 is formed in the via hole 302a. The wiring layer 311 is formed on the first surface of the insulating layer 301, and the wiring layer 312 is formed on the second surface of the insulating layer 302. Then, it roughens as needed.

Subsequently, in step S14 of FIG. 5, an external connection terminal is formed in the outermost layer.

Specifically, after the solder resist layers 331 and 332 are formed by coating or lamination, as shown in FIG. 15, the openings 331a and 332a are formed in the solder resist layers 331 and 332 by a predetermined lithography process. ). Portions of the wiring layers 311 and 312 are exposed as pads by the openings 331a and 332a. Then, as needed, these pads are surface-treated, such as Ni / Au plating and OSP (Organic Solderability Preservative). In addition, in this embodiment, although the opening 331a, 332a is formed after formation of the soldering resist layers 331, 332, it is not limited to this. For example, the solder resist layers 331, 332 are selectively formed in a state where the mask material is provided at the positions of the openings 331a, 332a in advance, and the solder resist layers 331 having the openings 331a, 332a from the beginning. , 332 may be formed.

Subsequently, the solder paste is printed and reflowed to form external connection terminals 331b and 332b (solder bumps) in the openings 331a and 332a. External connection terminals 331b and 332b are located on the pad. Thereby, the wiring board 1000 (FIG. 1) is completed. Moreover, as needed, external processing, curvature correction, energization inspection, external appearance inspection, or final inspection are performed.

The manufacturing method of this embodiment is suitable for manufacture of the wiring board 1000. With such a manufacturing method, a good wiring board 1000 can be obtained at low cost.

As mentioned above, although the wiring board which concerns on embodiment of this invention, and its manufacturing method was demonstrated, this invention is not limited to the said embodiment. For example, it can also be modified and carried out as follows.

In the said embodiment, although the presence density of the conductor in the high density conductor area | region R2 is larger than the presence density of the conductor in the low density conductor area | region R1 by the difference of this wiring layer number, it is not limited to this. . For example, due to the difference in the number of via conductors or the difference in the line width and the pitch of the conductor pattern, the presence density of the conductor in the high density conductor region R2 is the value of the conductor in the low density conductor region R1. It may be larger than the density of existence.

The via conductors 121, 122, 221, 222, 321, and 322 may be conformal vias, not field vias. However, in order to improve impact resistance, a field via is preferable. Further, the field vias can be formed to be stacked. Therefore, in order to raise the degree of freedom of design, a field via is preferable.

As shown in FIG. 16, the second rigid wiring board 20 may be a wiring board in which the electronic component 500 is incorporated. The second rigid wiring board 20 may incorporate a plurality of electronic components.

As shown in FIG. 17, a plurality of second rigid wiring boards 20 may be built in one accommodation space R11 of the first rigid wiring board 10.

In the said embodiment, although the gap | interval of the board | substrate 100 and the 2nd rigid wiring board 20 was filled with resin which flowed out from the upper insulating layer, it is not limited to this. For example, you may fill resin with the resin etc. which were prepared separately in the clearance gap before forming an upper insulating layer. In this case, it is effective to use a dispenser or the like to inject (fill) the resin. Moreover, you may temporarily fix the 2nd rigid wiring board 20 with an adhesive agent before forming an upper insulating layer.

The conductor pattern in the wiring board 1000 may have the form which fans out from a component connection terminal (for example, external connection terminal 331b) to a board connection terminal (for example, external connection terminal 332b).

As shown in FIG. 18, the 1st rigid wiring board 10 and the 2nd rigid wiring board 20 may have a wiring layer only on one side.

As shown in FIG. 18, only the wiring layer 214 on one main surface of the second rigid wiring board 20 is connected to the wiring layer of the first rigid wiring board 10 via the via conductor 122 of the inner layer of the wiring board 1000. 112) may be electrically connected.

As shown in FIG. 18, even when the wiring board 1000 and the first rigid wiring board 10 cannot be distinguished and substantially coincide with each other, in the inner layer of the wiring board 1000 (the first rigid wiring board 10), Since the first rigid wiring board 10 and the second rigid wiring board 20 are electrically connected to each other by the via conductor 122, the first rigid wiring board 10 and the second rigid wiring board 20 are protected against external shocks or the like. Connection reliability is high.

The shape and size of the accommodation space R11 are arbitrary. However, in positioning the 2nd rigid wiring board 20, the shape and size corresponding to the 2nd rigid wiring board 20 are preferable.

The accommodation space R11 is not limited to the through hole. For example, as shown in FIG. 19, the accommodating space R11 may be a recessed part.

In the said embodiment, the board | substrate 100 consists of five layers of prepreg (insulating layers 100a-100e). However, it is not limited to this and, for example, as shown in FIG. 19, the board | substrate 100 may be a single board | substrate (for example, epoxy resin etc.).

Regarding other points, in the above embodiment, the position, shape, material, size, pattern, number of layers, and the like of each component can be arbitrarily changed without departing from the spirit of the present invention.

The formation method of the accommodation space R11 is arbitrary. The accommodation space R11 may be formed by etching or the like, for example.

The manufacturing method of the present invention is not limited to the contents and the order shown in the flowchart of FIG. 5, and the contents and the order can be arbitrarily changed without departing from the spirit of the present invention. Moreover, you may abbreviate | omit an unnecessary process according to a use etc.

For example, the formation method of a conductor pattern or a conductor for a connection is arbitrary. For example, the conductor pattern is formed by a method in which any one or two or more of the panel plating method, the pattern plating method, the full additive method, the semi-additive method (SAP) method, the subtractive method, the transfer method, and the tenting method are arbitrarily combined. You may also Hereinafter, as a representative example, the manufacturing method using the semiadditive process and the transfer method will be described. In addition, about the same or equivalent structure as the said embodiment, while using the same code | symbol, the description is abbreviate | omitted or simplified.

<Manufacturing method using the semi additive method>

In the manufacturing method using the semiadditive process, for example, the second rigid wiring board 20 is disposed in the through hole 20b (accommodating space R11) of the insulating layers 100a to 100e, similarly to the process of FIG. 7. 20, the insulating layer 101 is arrange | positioned at the 1st surface side of the insulating layer 100a and the 2nd rigid wiring board 20, and the insulating layer 100e and the 2nd rigid wiring board 20 are shown. The insulating layer 102 is arrange | positioned at the 2nd surface side of the.

Subsequently, hot pressing is applied to apply a force in the direction of the arrow shown in FIG. As a result, the insulating layers 100a to 100e are integrated to form the substrate 100. In addition, the gap between the substrate 100 and the second rigid wiring board 20 is filled with the resin 20a flowing out from the surrounding insulating layers (insulating layers 100a to 100e, insulating layers 101 and 102, and the like). .

Subsequently, as shown in Fig. 22, for example, by irradiation of CO ₂ laser to form a via-hole (101a, 102a) and the through hole (10a). Then, desmear and soft etch are performed as needed.

Subsequently, as shown in FIG. 23, electroless copper plating is performed on the first and second surfaces of the insulating layers 101 and 102, and the plating is performed in the through hole 10a and on the insulating layers 101 and 102. The film 130 is formed.

Subsequently, as shown in FIG. 24, the patterned plating resist 131 is formed on the plating film 130 formed on the insulating layers 101 and 102. Then, as shown in FIG. The plating resist 131 has an opening 131a.

Subsequently, as shown in FIG. 25, electrolytic copper plating is performed to the plating film 130 in which the plating resist 131 was formed, and the plating film 132 which coats the plating film 130 is formed. The plating film 132 is formed in the opening part 131a of the plating resist 131.

Then, as shown in FIG. 26, after removing (peeling) the plating resist 131, the part (exposed part) of the plating film 130 which is not covered with the plating film 132 by etching, for example. Remove it. Thereby, as shown in FIG. 27, the conductor pattern which has a 2-layered structure of the plating film 130 and the plating film 132 is formed on the insulating layers 101 and 102, respectively. As a result, the first rigid wiring board 10 incorporating the second rigid wiring board 20 is completed.

Subsequently, when the insulating layers 301 and 302 and the wiring layers 311 and 312 are formed on the first and second surface sides of the first rigid wiring board 10 in the order described in the above embodiment, the wiring board shown in FIG. 1 ( 1000) is completed.

<Manufacturing method using the transcription method>

In the manufacturing method using the transfer method, for example, as shown in FIG. 28, a set of stainless steel sheets 141 and 142 are prepared. The stainless steel sheets 141 and 142 each have a conductor pattern 150 made of electrolytic copper on its surface. In the transfer method, the conductor pattern is formed using this conductor pattern 150.

Specifically, for example, similarly to the process of FIG. 21, the insulating layers 100a to 100e (substrate 100), the second rigid wiring board 20, and the insulating layers 101 and 102 are hot pressed to integrate them. Then, as shown in FIG. 28, stainless steel sheets 141 and 142 are disposed so that the surfaces on which the conductor patterns 150 are formed face the insulating layers 101 and 102, respectively.

Subsequently, a press for applying a force in the direction of the arrow shown in FIG. 29 is performed. As a result, the conductor pattern 150 is transferred to the insulating layers 101 and 102.

Subsequently, as shown in Fig. 30, for example, by irradiation of CO ₂ laser to form a via-hole (101a, 102a) and the through hole (10a). Then, desmear and soft etch are performed as needed.

Subsequently, as shown in FIG. 31, electroless copper plating is performed on the first and second surfaces of the insulating layers 101 and 102, and the plating is carried out in the through hole 10a and on the insulating layers 101 and 102. The film 151 is formed.

32, the patterned plating resist 152 is formed on the plating film 151 formed on the insulating layers 101 and 102. Then, as shown in FIG. The plating resist 152 has an opening 152a. Then, the plating film 153 is formed by electrolytic copper plating on the plating film 151 on which the plating resist 152 is formed. The plating film 153 is formed in the opening 152a of the plating resist 152.

Subsequently, as shown in FIG. 33, after removing (peeling) the plating resist 152, the part (exposed part) of the plating film 151 which is not covered with the plating film 153 by etching, for example. Remove it. Thereby, as shown in FIG. 34, the conductor pattern which has a 3-layered structure of the conductor pattern 150, the plating film 151, and the plating film 153 is formed on the insulating layers 101 and 102, respectively. As a result, the first rigid wiring board 10 incorporating the second rigid wiring board 20 is completed.

Subsequently, when the insulating layers 301 and 302 and the wiring layers 311 and 312 are formed on the first and second surface sides of the first rigid wiring board 10 in the order described in the above embodiment, the wiring board shown in FIG. 1. 1000 is completed.

The manufacturing method using the semiadditive process or the transfer method demonstrated above is suitable for manufacture of the wiring board 1000. FIG. If it is such a manufacturing method, the favorable wiring board 1000 will be obtained at low cost.

In the above embodiment, the wiring layer 112 (first wiring layer) and the wiring layer 214 (second wiring layer) are connected by the via conductor 122 (first connection conductor), and the wiring layer 111 (third wiring layer) And the wiring layer 213 (fourth wiring layer) are connected by the via conductor 121 (second connection conductor). The present invention is not limited to this, and the wiring layer 112 (first wiring layer) and the wiring layer 214 (second wiring layer), or the wiring layer 111 (third wiring layer) and the wiring layer 213 (fourth wiring layer) are May be connected by a through-hole conductor (a conductor for first connection and a conductor for second connection).

When manufacturing a circuit board having such a through-hole conductors, the example was subjected to the press process, like the process of FIG. 9, as shown in Fig. 35, for example, by irradiation of CO ₂ laser, via-holes (101a, 102a and through holes 10a and 11a are formed. Then, desmear and soft etch are performed as needed.

Subsequently, a plating film is formed on the entire surface of the first and second surfaces by panel plating, and the plating is performed by a predetermined lithography process (for example, pretreatment, lamination, exposure, development, etching, thin film, etc.). The film is patterned. Thereby, as shown in FIG. 36, the 1st rigid wiring board 10 which has the through-hole conductor 154 is manufactured.

In the first rigid wiring board 10, the wiring layer 112 (first wiring layer), the wiring layer 214 (second wiring layer), the wiring layer 111 (third wiring layer), and the wiring layer 213 (fourth wiring layer) are It is electrically connected by the plating film (through hole conductor 154) formed in the inside of the through hole 11a.

As mentioned above, although embodiment of this invention was described, various corrections and combinations required by a design convenience and other factors are described in the invention described in the Claim, and the form for implementing an invention. It is to be understood that it is included within the scope of the invention corresponding to the specific embodiment.

Industrial availability

The wiring board according to the present invention is suitable for a circuit board of an electronic device. Moreover, the manufacturing method of the wiring board which concerns on this invention is suitable for manufacture of the circuit board of an electronic device.

10: first rigid wiring board
10a: through hole
10b: through hole conductor
10c: resin
11a: through hole
20: second rigid wiring board
20a: Resin
20b: through hole
100: substrate
100a-100e: insulation layer
101, 102: insulation layer
101a: Via Hole
102a: via hole
111: wiring layer
112: wiring layer
121: via conductor (second connection conductor)
122: via conductor (first connection conductor)
154: through hole conductor
200: substrate
200a: through hole
200b: through hole conductor
200c: Resin
201, 202: insulation layer
201a, 202a: Via Hole
211 and 212: wiring layer
213: wiring layer
214: wiring layer
221, 222: via conductor
301: insulating layer (second interlayer insulating layer)
302: insulating layer (first interlayer insulating layer)
301a, 302a: Via Hole
311, 312: wiring layer
321, 322: Via conductor
331 and 332: solder resist layer
331b, 332b: external connection terminal
500: electronic components
1000: wiring board
R1: low density conductor area
R2: high density conductor area
R11: accommodation space

Claims (11)

A first rigid having a substrate having a receiving space, a first insulating layer formed on the substrate so as to close an opening of the substrate formed by the receiving space, and a first wiring layer formed on the first insulating layer. Wiring board,
A second rigid wiring board having a second wiring layer on a main surface thereof and accommodated in the accommodation space;
A first connection conductor connecting the first wiring layer and the second wiring layer;
A wiring board having a first interlayer insulating layer formed on the first wiring layer. The method of claim 1,
The first insulating layer is made of prepreg,
A resin flowed out of the first insulating layer is filled in the gap between the first rigid wiring board and the second rigid wiring board. The method according to claim 1 or 2,
The existence density of the conductor in a said 2nd rigid wiring board is higher than the existence density of the conductor in a said 1st rigid wiring board, The wiring board characterized by the above-mentioned. The method according to claim 1 or 2,
The second rigid wiring board is a multilayer wiring board including a plurality of wiring layers including the second wiring layer,
The total number of the wiring layers of the second rigid wiring board is larger than the total number of wiring layers including the first wiring layer of the first rigid wiring board. The method according to claim 1 or 2,
The second rigid wiring board is a multilayer wiring board including a plurality of wiring layers including the second wiring layer,
The thickness of at least one wiring layer of the second rigid wiring board is smaller than the thickness of the wiring layer of the first rigid wiring board. The method according to claim 1 or 2,
The said 1st connection conductor is a via conductor formed in the said 1st insulating layer, The wiring board characterized by the above-mentioned. The method according to claim 6,
And the first connection conductor is a filled via. The method according to claim 1 or 2,
The said 1st connection conductor is a through-hole conductor which penetrates the said 2nd rigid wiring board and a said 1st insulating layer, The wiring board characterized by the above-mentioned. The method according to claim 1 or 2,
The accommodation space is a through hole,
The first rigid wiring board has a second insulating layer formed on the substrate so as to block the other opening of the substrate formed by the accommodation space, and a third wiring layer formed on the second insulating layer. ,
The second rigid wiring board has a fourth wiring layer on a main surface on the side opposite to the main surface on which the second wiring layer is formed,
In addition, the said wiring board,
A second connection conductor connecting the third wiring layer and the fourth wiring layer;
And a second interlayer insulating layer formed on the third wiring layer. Arranging a second rigid wiring board having a second wiring layer on a main surface in an accommodation space provided on the substrate of the first rigid wiring board;
An insulating layer is formed on the substrate and the second rigid wiring board, a first via hole is formed in the insulating layer, a first connecting conductor is formed in the first via hole, and a first on the insulating layer is formed. In the manufacturing method of the wiring board which comprises manufacturing the said 1st rigid wiring board which has the said 1st wiring layer and accommodates the said 2nd rigid wiring board inside by forming a wiring layer,
The first via hole is formed in the inner layer of the wiring board,
The said 1st wiring layer and the said 2nd wiring layer are electrically connected by the said 1st connection conductor, The manufacturing method of the wiring board characterized by the above-mentioned. 11. The method of claim 10,
And pressing the insulating layer to flow resin out of the insulating layer and filling the gap between the substrate and the second rigid wiring board.

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